Operation CHARM: Car repair manuals for everyone.

Cooling System: Testing and Inspection

CHECKING COOLING SYSTEM
1. Bring engine to operating temperature

WARNING: The cooling system is pressurized when the engine is warm. When opening the expansion tank, wear gloves and other appropriate protection, cover the cap using a cloth, and open carefully to relieve system pressure slowly.





2. Connect cooling system tester tool No. VW 1274, or equivalent, to expansion tank using adapter tool No. 1274/1, or equivalent.
3. Operate hand pump on tester to pressurize cooling system to approx. 1.0 bar (14.5 psi).
3. If pressure does not hold:
- Locate and repair leak in cooling system.

CHECKING PRESSURE RELIEF VALVE IN CAP





1. Screw cap onto cooling system tester tools No. VW 1274 using adapter 1274/1, or equivalents.
2. Operate hand pump to build pressure.
3. Pressure relief valve must open at 1.2-1.5 bar (17-22 psi).